This application is a 371 of PCT/EP02/06189 filed Jun. 6, 2002.
This invention relates generally to the cosmetics field and, more particularly, to new ternary mixtures of surfactants and to their use for the production of body care products.
Alkyl oligoglucosides are nonionic surfactants which have acquired particular significance in recent years by virtue of their particular dermatological compatibility. Another advantage of this group of compounds is that, although they do foam to an extent matched only by anionic surfactants, they can be combined far better with other surfactants through the absence of ionic groups.
Accordingly, various surfactant mixtures involving alkyl oligoglucosides are known from the prior art, combinations with a large number of anionic and amphoteric surfactants being preferred from the performance perspective. Thus, ternary combinations of alkyl oligoglucosides, alkyl ether sulfates and betaines, optionally with other cosurfactants, such as fatty alcohol polyglycol ethers, amine oxides, fatty acid amidoamines or alkyl sulfates, have been repeatedly recommended for use in manual dishwashing detergents [EP 0341071 B2 (Unilever), EP 0664830 B1 (Cognis), WO 96/29385, WO 97/38072, WO 98/36043, WO 98/46721 (all Colgate)]. The same mixtures are also used in cleaning products [EP 0670158 A2 (Colgate), WO 91/11506 (Henkel)] and in hair shampoos [DE 19723763 C1 (Goldwell)].
However, this is does not mean that all technical requirements have been satisfied. Mixtures containing anionic surfactants in particular have sometimes been found to show less than optimal dermatological compatibility, especially when used by consumers with sensitive skin. In addition, although highly concentrated flowable mixtures can be produced, such mixtures do form high-viscosity gel phases when diluted so that they are virtually impossible to handle. In addition, most of the known surfactant mixtures can only be protected against microbial infestation by the use of preservatives which is contrary to the concept of a particularly dermatologically compatible surfactant concentrate.
Accordingly, the problem addressed by the present invention was to provide surfactant mixtures which, besides good foaming and cleaning properties, would show improved dermatological compatibility. The mixtures would also be protected against microbial infestation even without the addition of possibly irritating preservatives, so that they could also be used in particular for the production of baby care products. In addition, the preparations would be liquid or flowable even in highly concentrated form and, in particular, would not form any high-viscosity gel phases on dilution.